DirectoryEntrySync

Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The DirectoryEntrySync interface of the File System API represents a directory in a file system. It includes methods for creating, reading, looking up, and recursively removing files in a directory.

About this document

This document was last updated on March 2, 2012 and follows the W3C Specifications (Working Draft) drafted on April 19, 2011.

This specification is pretty much abandoned, having failed to reach any substantial traction.

Basic concepts

If you want to create subdirectories, you have to create each child directory in sequence. If you try to create a directory using a full path that includes parent directories that do not exist yet, you get an error. So create the hierarchy by recursively adding a new path after creating the parent directory.

Example

The getFile() method returns a FileEntrySync, which represents a file in the file system.  The following creates an empty file called seekrits.txt in the root directory.

var fileEntry = fs.root.getFile('seekrits.txt', {create: true});

The getDirectory() method returns a DirectoryEntrySync, which represents a file in the file system. The following creates a new directory called superseekrit in the root directory.

var dirEntry = fs.root.getDirectory('superseekrit', {create: true});

Method overview

DirectoryReaderSync createReader () raises (FileException);
FileEntrySync getFile (in DOMString path, in optional Flags options) raises (FileException);
DirectoryEntrySync getDirectory (in DOMString path, in optional Flags options) raises (FileException);
void removeRecursively () raises (FileException);

Methods

createReader()

Creates a new DirectoryReaderSync to read entries from this directory.

DirectoryReaderSync createReader (
) raises (FileException);
Returns
DirectoryReaderSync
Represents a directory in a file system.
Parameter

None

Exceptions

This method can raise a FileException with the following codes:

Exception Description
NOT_FOUND_ERR The directory does not exist.
SECURITY_ERR The browser determined that it was not safe to look up the metadata. [ todo: Explain why ]

getFile()

Depending on how you've set the options parameter, the method either creates a file or looks up an existing file.

void getFile (
  in DOMString path, in optional Flags options
) raises (FileException);
Parameter
path
Either an absolute path or a relative path from the directory to the file to be looked up or created. You cannot create a file whose immediate parent does not exist. Create the parent directory first.
options
An object literal describing the behavior of the method. If the file does not exist, it is created.
Object literal Condition Result
create: true
exclusive: true
Path already exists An error is thrown.
create: true
exclusive: false
Path doesn't exist and no other error occurs A file is created. If a file already exists, no error is thrown.
create: false
(exclusive is ignored)
Path exists The file is returned.
create: false
(exclusive is ignored)
Path doesn't exist An error is thrown.
create: false
(exclusive is ignored)
Path exists, but is a directory An error is thrown.
Returns
FileEntrySync
Represents a file in a file system.
Exceptions

This method can raise a FileException with the following codes:

Exception Description
ENCODING_ERR The path supplied is invalid.
NOT_FOUND_ERR The path was structurally correct, but refers to a resource that does not exist.
NO_MODIFICATION_ALLOWED_ERR This is a permission issue. The target directory or file is not writable.
PATH_EXISTS_ERR The file already exists. You cannot create another one with the same path.
QUOTA_EXCEEDED_ERROR The operation would cause the application to exceed its storage quota.
SECURITY_ERR The application does not have permission to access the element referred to by path. [ todo: Explain why ]
TYPE_MISMATCH_ERR The path supplied exists, but it is not a directory.

getDirectory()

Creates or looks up a directory. The method is similar to getFile() with DirectoryEntrySync being passed.

void getDirectory (
  in DOMString path, in optional Flags options
) raises (FileException);
Parameter
path
Either an absolute path or a relative path from the directory to the file to be looked up or created. You cannot create a file whose immediate parent does not exist. Create the parent directory first.
options
An object literal describing the behavior of the method if the file does not exist.
Object literal Condition Result
create: true
exclusive: true
Path already exists An error is thrown.
create: true
exclusive: false
Path doesn't exist and no other error occurs A directory is created. If a file already exists, no error is thrown.
create: false
(exclusive is ignored)
Path exists The directory is returned.
create: false
(exclusive is ignored)
Path doesn't exist An error is thrown.
create: false
(exclusive is ignored)
Path exists, but is a directory An error is thrown.
Returns
DirectoryEntrySync
Represents a directory in a file system.
Exceptions

This method can raise a FileException with the following codes:

Exception Description
ENCODING_ERR The path supplied is invalid.
NOT_FOUND_ERR The path was structurally correct, but refers to a resource that does not exist.
NO_MODIFICATION_ALLOWED_ERR This is a permission issue. The target directory or file is not writable.
PATH_EXISTS_ERR The file already exists. You cannot create another one with the same path.
QUOTA_EXCEEDED_ERROR The operation would cause the application to exceed its storage quota.
SECURITY_ERR The application does not have permission to access the element referred to by path. [ todo: Explain why ]
TYPE_MISMATCH_ERR The path supplied exists, but it is not a directory.

removeRecursively()

Deletes a directory and all of its contents. You cannot delete the root directory of a file system.

If you delete a directory that contains a file that cannot be removed or if an error occurs while the deletion is in progress, some of the contents might not be deleted. Catch these cases with error callbacks and retry the deletion.

void removeRecursively (
)  raises (FileException);
Parameter

None

Returns

void

Exceptions

This method can raise a FileException with the following codes:

Exception Description
NOT_FOUND_ERR The target directory does not exist.
INVALID_STATE_ERR This directory is not longer valid for some reason other than being deleted.

[todo: Explain more ]

NO_MODIFICATION_ALLOWED_ERR One of the following is not writable: the directory, its parent directory, and some of the content in the directory.
SECURITY_ERR The application does not have permission to access the target directory, its parent, or some of its contents.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 13webkit Not supported Not supported Not supported Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support Not supported 0.16webkit Not supported Not supported Not supported Not supported

See also

Specification: File API: Directories and System SpecificationWD

Reference: File System API

Introduction: Basic Concepts About the File System API

Document Tags and Contributors

Contributors to this page: Sheppy, grendel, kscarfone, teoli
Last updated by: kscarfone,